Objective:
Hysteroscopy is the second most often performed endoscopic procedure in
gynaecology and is mostly part of any specialization program for gynaecology.
It is to be expected that training on a reasonably realistic simulator could substantially contribute to reduce the rate of complications. The simulator
will allow realistic real-time visualization of the intervention scene
including changes due to surgical actions and the control of the hydrometra
by manipulating the liquid influx and efflux as well as realistic tactile sensation.

The following components provided by all partners will be integrated
into the simulator:

Visualization algorithms for reasonably realistic presentation of the interventional field

Generation of anatomical models for the simulation, covering a possibly large range of pathologies

Clinical evaluation will be carried out in order to gain insight into which level of realism is needed to actually reach the goals of efficient surgical training on VR-based trainer, with special emphasis on visual fidelity and the presence and quality of force feedback.

Objective:
A basic requirement in the complete texturing solution for the
hysteroscopic simulator is the ability to texture the surfaces and
under surfaces of the uterus and pathologies. As the texture can vary
substantial over the life cycle of the uterus and with different
pathologies, a texturing approach that allows for easy user
interaction has been developed. This makes it possible for a novice
user to design their own surgical scenarios with an evolving library
of textures.

The interactive 3D surface texturing performs automatic mesh cutting
and parameterisation. This technique provides a viable mapping between
a 2D texture and a 3D surface, with the aim of reducing
distortion. This technique also allows arbitrary textures of any size
to be placed over a 3D surface. As it is the mesh parameterisation
that defines the mapping, a texture can be scaled, rotated and
translated over the surface interactively. With this kind of approach
what has to managed are the cuts, as they disrupt the surface
texture.

Objective:
In a realistic hysteroscopic simulator special interest has to be devoted
to the simulation of intra-uterine bleeding, influencing the visibility
of the surgical scene, until the correct adjustment of the inflow and outflow
valves on the instrument are performed by the surgeon.

The aim of this project is to develop a computer model that can produce a
visually appealing reconstruction of bleeding for hysteroscopic simulator.
Therefore, our task incorporates the needs for real-time synthesis and
responsiveness of the model to any actions introduced by the surgeon to the
dynamic virtual reality environment.

The problem that was presented, was that they required realistic
texture maps for their 3D model. They had sample textures of
particular types of marble that they wanted to use, but
unfortunately due to circumstances, these were not ideal textures
from which to synthesis texture maps. Most had unwanted
reflections from not using diffuse lighting during
photography. But in the most extreme cases, the marble had
suffered a great deal of weathering, resulting in a high density of
cracks and fractures over the sample texture. These flaws in the
sample texture needed to be absent in the synthetic texture.

The solution to the problem was to use the fast version of Paget and Longstaff's texture synthesis algorithm. Because Paget and Longstaff's algorithm is pixel based, not patch based, it was easy to incorporate an arbitrary mask over the input sample texture. This mask did not affect the sampling procedure, nor did it effect the multi-resolution modelling, as that was done via quad-tree decimation. This meant that the flaws in the input sample texture could be masked out while still preserving the long and short range texture characteristics.